Method of making metallurgical coke briquettes from coal, raw petroleum coke, inert material and a binder

ABSTRACT

The process comprises: mixing selected carbonaceous particles with a plasticizer; heating the particles and the plasticizer to a suitable temperature; compressing the plasticized particles while they are hot into green bodies of desired shape and specified maximum porosity and minimum density; and carbonizing the formed green bodies, employing a controlled carbonization process. Care it taken to avoid any substantial amount of oxidation of the particles and/or of the formed green bodies during most of the aforesaid heating, pressing and carbonizing steps, particularly while the particles or bodies are at substantially elevated temperatures. Other elements of the process will become apparent from a detailed reading of this specification.

United States Patent [72] Inventor Joseph J- Patel 2,808,370 10/1957Bowers 201/22 Skokie, 111.; 3,010,882 11/1961 Barclaet a1 201/6 U XFrederick L. Shea, Jr., Johnson City, 3,018,227 1/1962 Baum et a1 201/23Tenn.; Richard L. Stec, Chicago, 111. 3,018,226 l/ 1962 Batchelor et a1201/5 [21] Appl. No. 630,373 3,316,155 4/1967 Holowaty et a1 201/6 graiPrimary Exammer--Norman Yudkoff 73] Assignee Great Lakes CarbonCorporation Asmmm Edwards New York, NY. Anorneya ace eyer m [54] METHODOF MAKING METALLURGICAL COKE BRIQUETTES FROM COAL, RAW PETROLEUMABSTRACT: The process comprises: mrxmg selected car- COKE, INERTMATERIAL AND A BINDER bonaceous particles wlth a plastlcrzer; heatingthe particles 30 Claims 3 Drawing Figs. and the P13916126! to a suitabletemperature; compressing the plastlclzed particles while they are hotInto green bodies of [52] US. Cl 201/6, desired shape and ifi d maximumporosity and minimum 2on8 201/22' 201mg 264/29 density; and carbonizingthe formed green bodies, employing [511 int. Cl ClOb 55/02 a controlledcarbonization process Cal-e it taken to avoid any [50] Field of Search201/5, 6, 7, Substantial] amount f oxidation f the panicles and/or f the8, 21-24, 34, 42; 264/29; 44/ 23 formed green bodies during most of theaforesaid heating, pressing and carbonizing steps, particularly whilethe particles [56] References Cited or bodies are at substantiallyelevated temperatures. Other UNITED STATES PATENTS elements of theprocess will become a arent from a detailed PP 2,336,151 12/1943 Kruppa201/6 X reading ofthis specification.

Fits C 571F021?! UVER T FTMOS'PHEEE E Ffiflfi i DRrg 7 J26 paw/av? J P1K72! A6 RETURN F4 uE p 85 7702 L I? gap wk 51/00: snv 7 gigs "2.-wave/{7- 115051 2 xwve-s Crczaw r; a; 00s n 7 l "Jrnvnoron &(F//v*s g4.10%) I 4x 5 gzf 76 5:42 m4 v: J34 8) "5H! r l 14 M 0 7L 44: Jan?twyiya plp 0? GW 1] k ily-1,10 Jfi'P/VR/VT; Q CNIMEIR j q NlTER/NGi'l/MP k E HaPPA'fi' FEEDR F0 P 55 I R R In? ELOWER 2 M X/E 00F FaRMtDP/eaauer $2111 Q i Lil's [5.111- 5 IL} jg H519 rs; J/VC/fT 20 X l k N Z]cmvvs Ya? 5/e/07" J8 & n PRESS 8 -Cfl/P-B0/V/ZER 2 a Mira/P94 awas- TQM""Faknsa (O/r5 P/PaaL/C' PATENTEDuuv 9 IBTI SHEET 1 [1F 3 PAIENIEfluuv"9 ISTI SHEET 2 [IF 3 I INERT MATERIAL SUCH I AS ANTHRACITE OR RAWPETROLEUM COKE HAVING A VM OF AT F'IE.E

BITUMINOUS COAL OR PARTIALLY DEVOLATILIZED BITUMINOUS COAL HAVING A VMOF AT LEAST I5% LEAST 8% COKE BREEZE 6 z I iz Q 0| 4, 0 "*0 6 BLEND,(IFNECESSARY) CRUSH TO AT LEAST SUBSTANTIALLY IOO/ MINUS INCH PARTICLESIZE, OPTIONALLY DRYING THE STARTING MATERIALIS) BEFORE 0R AFTERBLENDING AND MILLING.

HEAT PARTICLES T0 TEMPERATURE BELOW THEIR FUSION TEMPERATURE BUT TO ATEMPERATURE AT LEAST AS HIGH AS ABOUT 300 F, BY HEATING IN AN INERT GASSYSTEM.

REMOVE PARTICLES FROM HEATER,MAI AN INERT ATMOSPHERE.

NTAINING BUT BELOW THE FUSION TEMPERATURE PARTICLES OF THE BASEMATERIALIS).

OF THE GREATER THAN 37 l BRIQUET OR PRESS THE PLASTICIZED MIX WHILE ITIS STILL ABOVE ABOUT 300F TYPICALLY LIMITING THE RETENTION TIME ATMAXIMUM TEMPERATURE PRIOR TO PRESSING TO 5 MINUTES, EMPLOYING PRESSURESABOVE 500 PSI AND PRESSING TIMES TYPICALLY LESS THAN 2 SECONDS, TOPRODUCE FORMED GREEN BODIES WHICH HAVE A.D. OF AT LEAST 0.85 AND APOROSITY NO EMPLOYING A RAPID CAR (8 HOURS OR LESS) CARBONIZE THE FORMEDGREEN BODIES,WITHOUT SUBSTANTIAL COOLING TO A LOW VM CONTENT;

BONIZATION PROCESS.

PAIENTEDunv 9 |97I RAW PETROLEUM COKE HAVING A VM OF AT LEAST 8/o SHEET3 BF 3 I INERT MATERIAL SUCH I AS ANTHRACITE OR I COKE BREEZE JBITUMINOUS COAL OR PARTIALLY DEVOLATILIZED BITUMINOUS COAL HAVING A VMOF AT LEAST |5/o BLEND,(IF NECESSARY) CRUSH TO AT LEAST SUBSTANTIALLYIOO/o MINUS V8 INCH PARTICLE SIZE, OPTIONALLY DRYING THE STARTING (S)BEFORE OR AFTER BLENDING AND MIX PARTICLES WITH I-8 PPH OF PLASTICIZERAND HEAT SAID MIXTURE TO A TEMPERATURE AT LEAST AS HIGH AS ABOUT 300FBUT BELOW THE FUSION TEMPERATURE OF THE PARTICLES OF THE BASEMATERIAL(S).

CARBONIZE THE FORMED GREEN BODIES,WITHOUT SUBSTANTIAL COOLING, TO A LOWVM CONTENT; EMELOYING A RAPID CARBONIZATION PROCESS. (8 HOURS OR LESS)FIE. 3

METHOD OF MAKING METALLURGICAL COKE BRIQUE'I'IES FROM COAL, RAWPETROLEUM COKE, INERT MATERIAL AND A BINDER BACKGROUND OF THE INVENTIONl. Field of the Invention This invention relates to a novel process forproducing coke suitable for use in cupolas, blast furnaces and othermetallurgical operations.

2. Description of the Prior Art Typically the prior art cokes suitablefor the above purposes have been produced in byproduct coking ovens bycoking a blend of high and low-volatile bituminous coals, or by coking ablend of such coals along with other suitable ingredients such as pitchand anthracite; the types, number and amounts of the components havingbeen selected according to the ultimate properties desired in the coke.The size and strength of the coked product has been nonuniform-so thatsome of the product has been of desired size and strength; some has beenof the desired size but of inferior strength as indicated by poorshatter and tumbler values; some as been undersize, etc. Such variationsmake good cupola operation difficult, particularly where large volumeproduction is concerned or where close limits in metal composition andtemperature are necessary, such as when castings are being made forcritical applications.

SUMMARY OF THE INVENTION It is an object of the present invention toproduce a metallurgical coke by a technique completely different fromthe aforedescribed conventional coking operation carried out inbyproduct coking ovens.

It is another object of this invention to produce coke of substantiallyuniform size and strength and all of which is suitable for metallurgicalpurposes, as contrasted with coke nonnally produced in a byproduct cokeoven which is characterized by an appreciable amount of undersizematerial.

It is an additional object of this invention to produce coke whichpossesses porosity and density characteristics which are closelycontrolled, and which can also be very low in ash content. Such cokesare well suited for use in the phosphorus and calcium carbide industriesas a reductant, and as a carbonaceous aggregate in the production ofSoderberg anodes or prebaked anodes for the aluminum industry.

It is yet another object of this invention to produce coke in a periodof time which is substantially shorter than the times employed toproduce coke by conventional byproduct coking oven techniques, whichtypically require about 18-24 hours.

It is still another object of this invention to produce coke by aprocess which is substantially continuous in nature and which typicallyrequires less manpower and maintenance costs than are required by thebyproduct oven coking technique, which may be referred to as a "multiplebatch" process.

The process, in a preferred embodiment, comprises producingmetallurgical coke from two main active particulate carbonaceousingredients, viz coal and a raw uncalcined coke made by coking a heavyliquefiable hydrocarbon to a volatile matter content exclusive of waterof about 8 percent to about 20 percent e.g. raw petroleum coke, and aplasticizing agent for one or both of these materials. Minor amounts (upto about percent by weight, of the total particulate blend) of inert(essentially nonfusible during the coking process) materials such asanthracite, or coke breeze, or calcined petroleum coke, or poorly fusingor oxidized raw petroleum coke, or ores to be reduced in subsequent useof the coke may also be included in the fonnulation. In less preferredembodiments. the final coke may sometimes also be prepared from rawuncalcined coke as the sole active particulate starting material plus aplasticizing agent for same; or from raw or partially devolatilizedbituminous coal as the sole active particulute starting material plus aplasticizing agent for it. Generally and preferably. however, theinvention will be carried out using as the active particulate startingmaterial a blend of coal and raw uncalcined coke, 100 parts of blend inproportions of to 15 parts of the raw uncalcined coke and 15 to 85 partsof the coal. A very important part of the process is the use ofplasticizing agent(s), which agent(s), serve many functions, butprimarily to soften the particulate starting materials and to lower thetemperature(s) at which the main active particulate ingredient(s) may bepress-formed or briquetted to produce formed green bodies havingstrengths satisfactory for further processing and subsequent ultimateuse after being carbonized.

The starting raw uncalcined coke is preferably of the delayed coker"type made by coking a heavy, liquefiable petroleum hydrocarbon to avolatile matter (VM) content exclusive of water of from about 8 percentto about 20 percent, and more typically from about 1 1 percent to about16 percent; it is preferred, also, that it be able to fonn a button," asthis property is defined hereinafter in connection with the volatilematter content test, and that it have a VM content of at least about 10percent, particularly if the raw uncalcined coke is employed as the onlyactive particulate starting material. lts VM content may be as low as 8percent when used in admixture with coal.

The coal has a volatile matter content of from about 15 percent to about45 percent and may cover the low, medium and high-volatile coal range;if the coal has a VM content exceeding about 20 percent and is used asthe sole or major active particulate starting material, it is necessaryto subject the starting coal to an initial or preliminary partialdevolatilization step before it is used in the process and this isdiscussed in more detail hereinafter.

Other objects, and coincident advantages, and a complete understandingof the invention will be apparent to those skilled in the art after astudy of the drawings, and a reading of the specifications and claims.

BRIEF DESCRIPTION OF THE DRAWINGS It has been found that the foregoingobjects and advantages are achievable by carrying out the processes setforth in the schematic drawing of FIG. 1, or in block or outline fonn inthe accompanying drawings of FIGS. 2 and 3.

DETAILED DESCRIPTION OF THE DRAWINGS AND OF THE PREFERRED EMBODIMENTS Asillustrated in FIG. 1, the starting particulate material(s) typicallyare stored in separate hoppers l, 2 and 3 and blended in a desiredproportion by means of controlled feeders. The materials in thesehoppers may be dewatered or partially dried if necessary. If notsufficiently dry, the starting material(s) or mixture is fed to a rotarydryer 4 prior to entering a pulverizer system. In the pulverizer or mill5 the starting material(s) or mixture is crushed, milled or ground(additionally mixed) to a typical particle size of substantially percentminus ls-inch if the particles are not already this size; however, theymay be coarser or finer than this. A screen 6 may be used to restrict orcontrol the size of the particles used in the subsequent steps of theprocess. However, particle sizing exceedingly fine, for example 100percent minus 325 mesh, (or even as fme as 50 percent minus 200 mesh) isgenerally avoided because unnecessary for optimum results and undulyexpensive; that is, it accomplishes nothing extra, adds to theprocessing costs, and can result in formed bodies which are undesirablydusty.

A conditioning temperature above about 300 F. and typically betweenabout 320 F. and about 500 F., more typically between about 340 andabout 450 F., but below that at which the particles readily fuse oragglomerate is generally employed prior to addition of the plasticizer.As illustrated in FIG. 1, the main or major portion of the heating ofthe particles to the desired temperature may be carried out byentrainment heating in an inert gas stream such as in conveying pipe 8,after the particles pass through surge bin 7, and weight feeder 7a andseal valve 7b. The heat for the entrainment heating system is providedby the combustion of gas in chamber 9 of the air-gas mixture from mixer10. The heated particles are then separated from the hot gases incyclone-collector or cyclone-separator it. As much time as is convenient(rapidly or slowly, as desired, or as best suited to process rates orthe equipment available) may be taken to reach the desired elevatedconditioning but nonfusing temperature. The particles may also be heatedin the mill 5, either entirely or partially or in many other waysprovided an inert atmosphere or an inert gas system is maintained toprevent excessive oxidation, which is generally detrimental tofusibility of the particles and strength of the finished product.

Cyclone-wparator 111 will typically have a high-separation efliciencysuch as in excess of about 95 percent. The separated solids are thenconveyed to mixer 17, where they are then mixed with the plasticizer,while the flue gases and residually entrained fines from thecyclone-separator 11 are directed elsewhere. They may be cycled backinto the process such as through a second cyclone-separator 12, whichtypically will be about 50 percent efflcient in separating the residualfines from the flue gases. Part of the residual fines, then, fromseparator 12 are cycled to mixer 17 while part also are cycled back tocombustion chamber 9 together with return flue gases. A portion of thegases from cyclone-separator 12 are recycled to combustion chamber 9 toprovide temperature control of the heating gases while excess gas from12 is vented to the atmosphere. Any fines in the exhaust gases vented tothe atmosphere may be disposed of by combustion or recovered, aftercooling, in a baghouse.

The heated particles from cyclone-separator 11 and some also fromseparator 12 are, as aforesaid, typically conveyed to a continuous mixer17, such as a pug mill or continuous mix muller. It should be apparentfrom FIG. 1 that the particles entering mixer 17 are in a heatedcondition. The particles are mixed in mixer I7 with a heated plasticizerfrom plasticizer tank 13, the temperature of the plasticizer in the tankbeing sufficiently high to substantially lower its viscosity but not sohigh as to boil or decompose it. This tank and/or the plasticizer withinsame may be heated, such as by means'of electric heater 14, or by othersuitable means such as hot oil or steam. A metering pump 15 may be usedto control the amount or proportion of plasticizer (typically from aboutI to about 8 percent and more preferably from about 2 to about 6 percentby weight of the particulate materials entering mixer 17 which is fed tomixer 17 to be mixed with the heated particles. This proportion ofplasticizer may also be expressed as parts per hundred (p.p.h.) parts ofparticulate materials. Auxiliary heating means 16 typically are used inthe plasticizer feed lines to the mixer to rapidly raise its temperatureto the approximate level of the particles. The heated plasticizer mayconveniently be sprayed onto the particles in mixer 17. Mixer l7typically will also be heated, such as by the burning of natural gas inair in chamber 18 and passing the heated gas to heater jacket 19, so asto keep the particles-plasticizer mix at the desired elevatedtemperature for molding or briquetting. This elevated temperature" is atleast as high as about 300 F. but is also below the fusion temperatureof the base solid carbonaceous material(s) before these material(s) aremixed with the plasticizer. The plasticizer and particles are typicallyrapidly mixed in a short period of time, such as in from about 0.5 toabout l minutes while they are still at an elevated temperature aboveabout 300 F. during which time the mix fuses or becomes plasticlike. Themix is then molded or briquetted, such as by a briquet press 20, beforeit is rendered nonplastic due to overheating (either timewise ortemperature wise). The retention time that the mixture of particles andplasticizer is maintained at maximum temperature prior to pressing isgenerally limited to no more than about minutes. (Typically the materialflows continuously through the mixer and a proportion of the totalretention time is required to complete mechanical mixing; the remainderis necessary to allow for interaction or alloying between theplasticizer and raw coke and/or raw coal, which interaction takes placein mixer 17 and also in hopper-feeder 20a both of which are maintainedunder substantially inert or nonoxidizing conditions.)

In the forming or briquetting step, the pressure employed is variabledepending on the temperature of the particles being formed, theformulation being processed, the type of press or forming operationused, etc.

The formed green bodies produced typically have an apparent density(A.D.) between about 0.85 and about 1.25 grams per cubic centimeter(g./cc.) and a porosity between about 8 percent and about 37 percent.After pressing. the hot formed green bodies are transferred, such as byconveyor 21 (which typically will also be housed in a substantiallyinert or nonoxidizing atmosphere) to a carbonizer 22 where they aregradually but rapidly heated (preferably 8 hours or less) in asubstantially inert atmosphere to the degree (e.g. typically l,000 F. to2,000 F.) that their volatile matter content is substantially reducedfrom the green state.

The foregoing described technique for carrying out the process is thatwhich is preferred, and is also that which is illustrated in the blockdrawing of FIG. 2. It should be apparent, however, that there areprocess techniques or variations which are somewhat different from theforegoing procedure but which are also within the scope of theinvention. The block drawing of FIG. 3 illustrates such an alternativetechnique. In this illustrated process the starting particulatematerials are first mixed with the plasticizer before being heated,rather than being separately heated before being mixed with theplasticizer. The entire mixture is then relatively rapidly heated duringwhich heating step the plasticizer alloys with the particulate startingmaterials. This heating step can conveniently be carried out whilesimultaneously mixing all of the materials and also while conveying thematerials to the fonning apparatus. In the heating step the mixture isheated to a temperature at least as high as about 300 F. but below thefusion temperature of the particles of the base coal and/or cokematerials, and the plasticized mixture, which has become fused orplasticlike, is briquetted or pressed while it is still above about 300F. and before it is rendered nonplastic. The retention time that themixture of particles and plasticizer is maintained at maximumtemperature prior to pressing is generally limited to no more than 5minutes. It will be noted that in this process variation the retentiontime at maximum temperature is sub stantially the same as in the processvariation of FIG. 2. It will be appreciated, however, that, because noelevated temperature conditioning step(s) are carried out, more time isgenerally required or employed in the heating step to get theplasticized mixture up to maximum temperature than in the heating stepof the plasticized mixture of FIG. 2. The briquetting and carbonizingsteps are then carried out in the same manner as for the process of FIG.2. It is important that the temperature of the plasticized particlesreach at least about 300 F. for any of the blends of this invention.Otherwise a poor briquetting operation follows and the strength of thecarbonized briquettes is poor. The maximum temperature(s) and retentiontime(s) at maximum temperature which may be employed will vary and mustbe adjusted for each type of formulation to be briquetted; but for anygiven formulation there must be close control of the time andtemperature conditions. Otherwise the mixture employed will not besoftened enough for satisfactory briquetting or will be overheated orheated too long and rendered nonplastic and unsatisfactory forbriquetting.

It should also be pointed out that the main function of the plasticizersdescribed herein is as such rather than as bindeis. In other words, theyare used mainly as processing aids in enabling the use oflower-pressures and temperatures in forming than would otherwise benecessary to produce strong green bodies. That they function as such isapparent from the fact that the plasticizer plus an inert such asanthracite, when heated to forming temperature, and pressed, does notyield a cohesive briquet; the active particulate material(s) alone whenprocessed in this same manner, e.g. heated and pressfonned, also do notbecome cohesive or yield a cohesive body. But the active particulatematerial(s) plus plasticizer when heated and processed in an identicalmanner do form cohesive bodies. Consequently, neither the plasticizernor the active particulate material(s) can be acting solely as binderduring the fonning step. Therefore, the plasticizers act as such, viz asplasticizers before the forming operation, rather than as a binder. Thisis not to say, however, that the plasticizers cannot be convertedpartially or largely to carbon (and thus function also as a binder)during the carbonization step.

Other process variations which are possible and which should be obviousare to heat the particulate starting material(s) (either the activeand/or the inert) separately from the plasticizer by techniques otherthan entrainment heating, such as by batch techniques or in a mill or ina mixer or in a fluidized bed, etc.; and then mix the plasticizer withthe heated particles. The particulate starting materials may alsoinitially be heated separately and to different temperatures before theyare blended with each other and with the plasticizer. If so, the inertmaterial may typically be heated to a higher temperature than the activematerial. The plasticizer may be separately heated or may receive partor all of its heat from the preheated particles. Other possible processvariations will be obvious to those skilled in the art.

In order that the invention may be completely understood the followingexamples are set forth:

EXAMPLE 1 Fifty parts of bituminous coal having a VM content of 26.1percent and 50 parts of raw petroleum coke having a VM content of 13.5percent stored in separate hoppers l and 2 as illustrated in FIG. 1 wereblended in these proportions by means of controlled feeders. The blendedmaterials contained about 5 percent moisture and were dried in rotarydryer 4 by subjecting them to a temperature of about 250 F. for about Iminutes. The dried mixture was then fed to a pulverizer system such asused in powdered coal burners. In the pulverizer or mill 5 the mixturewas milled or ground (and additionally mixed) to a particle size suchthat substantially 100 percent of the mixture could pass through a meshscreen (Tyler) (or roughly minus zit-inch). A screen 6 was used torestrict or prevent larger sized particles from entering the subsequentsteps of the process.

The main or major portion of the heating of the particles to the desiredtemperature was carried out by entrainment heating in an inert gasstream in conveying pipe 8, after the dried, milled and mixed particlespassed through surge bin 7, weight feeder 7a and seal valve 7b. Weightfeeder 7a was used to closely control the quantity of material enteringthe conveying pipe 8. In the present example, feeder 7a was set to admit4,640 pounds (:3 percent) of particulate material per hour to conveyingpipe 8. (Although illustrated as horizontal in FIG. I, it should beunderstood that conveying pipe 8 may be at any desired slope includingvertical, with the particles moving in a downward direction.) Conveyingpipe 8 was 2 feet in diameter and 2l feet long. The heat for theentrainment heating system was provided by the burning of natural gas incombustion chamber 9 of the air-gas mixture from mixer 10. Thecombustion chamber 9 was designed to provide 2.54 million B.t.u./hourheat release; 1.73 million Btu/hour of this being provided by theburning of 29 s.c.f.m. (standard cubic feet per minute) of natural gasin 290 s.c.f.m. of air from the air-gas mixer 10; and 0.81 millionB.t.u./hour of this being provided by the return and/or combustion ofhot flue gases and fines from the "Fines" cyclone-separator 12. Thenonoxidizing gas leaving combustion chamber 9 has an output temperatureof 800 F. and a rate of 7,950 cubic feet per minute (c.f.m. This rate offlow corresponds to a linear velocity of the gases in the pipe 8 ofabout 50 feet per second. The particles are conveyed in this gas streamand have an average retention time in the pipe of less than a secondwhile they are heated to such a temperature that after separation fromthe gases in the cycloneseparator ll they have a temperature of about400 F. (As previously indicated. although rapid heating rates arepreferred for maxlmum production, as much time as is convenient, rapidlyor slowly, as desired, or as best suited to process rates or theequipment available, may be taken to heat the particulate startingmaterials to the desired elevated, nonfusing temperature before they aremixed with the plasticizer. Also as previously indicated, entrainmenttype heating is not essential and the particles may be heated in themill 5, either entirely or partially or in many other ways, such as in afluid bed.)

The typical cyclone-separator 11 used is so designed as to have ahigh-separation efliciency, such as in excess of about percent, or about97 percent, for the size particles being processed. The separated solidsare then passed to mixer 17, (97 percent of 4,640 or about 4,500pounds/hour) where they are then mixed with the plasticizer, while theflue gases and residually entrained fines (about I40 pounds/hour) fromthe cyclone-separator 11 are directed elsewhere. In the processillustrated in FIG. 1 and the present example, they are utilized to agreat extent by being cycled at a flow rate of about 5,6 I0 c.f.m. backinto the process such as through a second cycloneseparator 12, whichtypically will be about 50 percent efficient in separating the residuallines from the flue gases. About half of the residual fines, then,(about 70 pounds/hour) from separator 12 are cycled to mixer 17; whilepart also (about 58 pounds/hour) are cycled back to combustion chamber 9together with return flue gases. Another minor part (about 12pounds/hour) are disposed of by combustion or recovered, after cooling,in a baghouse. A damper 12b is typically used to restrict the proportionof fines which are so processed and to favorably proportion thepercentage cycled back to combustion chamber 9. Seal valves 1 1a and 12afrom cyclones II and 12 permit the flow of solids and eliminate gas flowinto the mixer, the feed rate into the mixer being effectivelycontrolled by weight feeder 7a.

The heated particles from cyclone-separator 11 and a minor proportionalso from cyclone-separator 12 are, as aforesaid, conveyed to a mixer17. The heated particles were mixed in mixer 17 with a heatedplasticizer from plasticizer tank 13. the temperature of the plasticizerin the tank being sufiiciently high to substantially lower its viscositybut not so high as to boil or decompose it. This tank and/or theplasticizer within same was heated by means of heater 14. In the presentexample, the plasticizer used was thermal tar having the followingproperties:

Specific Gravity at 20/20 C.l.02

The viscosity of the thermal tar in Saybolt Universal Seconds at 210 F.was 95.

A metering pump 15 was used to control the amount or proportion ofplasticizer cycled into mixer 17 to be mixed with the heated particles.Preferably, as aforesaid, this will vary from 2 to about 6 parts byweight per hundred parts of the particulate materiaKs) entering mixer 17or will be from about I I to about 33 gallons per hour. In the presentexample 5 parts or percent thermal tar by weight was used. Auxiliaryheating means 16 were used in the plasticizer feed lines to the mixer inorder to rapidly raise the temperature of the plasticizer from 300 F. tothe approximate level (400 F.) of the particles and also the temperaturedesired for briquetting. These auxiliary heating means are used becauseit is preferred not to heat the plasticizer to this temperature levelfor too long a period of time prior to mixing it with the heatedparticles. The heated plasticizer of lowered viscosity may convenientlybe sprayed onto the particles in mixer 17. Mixer 17 is typically alsoheated by hot gases, such as from the burning of natural gas in chamber18 (e.g. 0.8 s.c.f.m. of natural gas in 8.8 s.c.f.m. ofair to provide51,170 B.t.u./hour), in heater jacket 19, so as to keep theparticles-plasticizer mix at the desired elevated temperature forpressure-forming or briquetting; the products of combustion from theheater jacket being vented to stack. The plasticizer and particles werethen rapidly mixed in mixer 17, which typically has a maximum retensiontime of about minutes and more typically about 10 minutes, and were thenpressure formed in double roll briquet press at a pressure of 28,000p.s.i., while at about the 400 F. temperature and before the alloyformed was rendered nonplastic, after which the hot formed green bodies(about 4,500 pounds/hour were passed, by conveyor 21, to a carbonizer 22where they were gradually heated in 6 hours in an inert atmosphere to amaximum temperature of 1,800 F.

The briquets produced were pillow shaped and were 3 inches long, 2inches wide and possessed a maximum thickness of 1% inches; it should,however, be appreciated that the green bodies of this invention can haveother shapes such as semlcylindrical, or tubular, or doughnut-shaped,etc; depending in large part upon the necessity or desirability ofproducing porosity in the packed bed of the furnace in which they areused. Such alternative shapes may also readily be resorted to in orderto facilitate rapid evolution of volatiles in the carbonizing step (andhence a rapid carbonizlng step) and, at the same time, the minimizationof flaws, or cracks or spalling, etc, during the carbonization step.Generally, however, the formed green bodies of the invention will be soshaped that at least one of its dimensions does not exceed about 2inches.

it will be noted that in the foregoing example 50 parts of raw petroleumcoke, 50 parts of coal, and 5 parts of plasticizer, by weight, wereused. Most typically and preferably in the present invention the activematerial(s) used will be a blend of coal and raw coke and this blendwill comprise from 15 to 85 percent of a coking coal, andcorrespondingly from 85 to 15 percent of raw coke (preferably rawpetroleum coke). As indicated in FIGS. 2 and 3, to these active basematerials may be added minor amounts ofinert.

The examples in the following table illustrate the effect of some of theprocessing variables of the present invention on the properties of theresultant carbonized bodies. The coal and the raw petroleum coke and theroll pressure employed were the same as used in example 1. Differentplasticizers were used, in varying amounts, as indicated in the table. Acarbonizing time of 6 hours was employed in each of the examples, usingan even upheat rate to a final temperature of l,762 F. in this period.

in the foregoing examples, as well as in example 1, regular size coaland coke materials were used. Regular" material is typified by thefollowing screen analysis:

Mesh Size Coal Petroleum Coke in. 10 m. 1.04 0.42

Coal Tar Properties 900 ccntipoises Specific Gravity, 25/25 C. BenzeneInsoluble, Wgt. Viscosity, 25 C. Distillation (D-20) Up to 517 F. 2.65%517 F.-680 F. 13.60% Residue, or above 680 F. 83.75%

Additional tests were carried out employing processing conditionssimilar to those set forth in table 1 but wherein the raw petroleum cokewas replaced with calcined petroleum coke; or wherein the plasticizerwas omitted; or wherein the coal as used was a high volatile coal andwas percent or more of the blend (it was not initially partiallydevolatilized before being used). In all instances unsatisfactoryresults were obtained.

As previously pointed out, the invention may be carried out by using theraw uncalcined coke as the sole active particulate starting material,said coke, when used alone, having a volatile TABLE I Modified Weightpercent Plastinizer p.p.h. Mix, tumbler test,

(parts per iundred temp, wgt. percent Apparent Example Coal Coke 01 coaland coke) F. +1" density .2 50 310 72. 1 1. 12 3 50 345 73. 1] 1. 14 450 348 79. 2 1. 12 5 50 352 72. 9 1. 15 6 50 402 86. 8 1. 20 7 50 44262. 2 1. 19 8 50 354 63. 2 1. 10 E) 26 340 80. 8 1. 33 10 25 356 81.6 1. 28 11 25 360 71. 7 1. 26 12 25 350 82. 3 1. 39 13 25 352 84. 2 1.33 14 0 437 60. 2 1. 40 15 0 370 56, 2 1. 42 16 0 434 56. 7 1. 44 17 0399 52. 6 1. 43 18 1 380 61. 3 1. 13 19 1 75 354 64. 7 1. 16 20 1 75 37660.1 1.11 21 1 75 408 66. 5 1. 12 22 l 100 340 59. 6 1. Q9 23 1 100 37455. 4 1. 06 24 l 100 384 53. 2 1.01 25 7 100 0 5.0, coal tar 512 57. 80.

1 Bituminous coal devolatilized to approximately 20% volatile mattercontent. 2 Mixture of bit misqs qsl s q e ilirs i 5 .1 .lqzzes ks qlisa.

matter content of at least about percent and ranging up to aboutpercent, and preferably about 1 1-16 percent, exclusive of water. Theraw coke referred to may be obtained as a fusible residue by the thermalcracking or coking of petroleum hydrocarbon oils, cracked asphalts,straight run asphalts, coal tar pitch, wood tar pitch, and the like. (Aspreviously indicated, however, an especially useful and preferred rawcoke is raw petroleum coke produced in a delayed coker.) Also, aspreviously pointed out, the invention may be carried out by using rawcoal or partially devolatilized coal as the sole active particulatestarting material, so long as its VM content does not exceed about 20percent. The use of raw coke alone or of coal alone (having a proper VMcontent) are illustrated in the examples of table I. As is apparent fromthe tumbler tests, however, mixtures of coal and raw coke result inhigher values and are, therefore, preferred in the processes of thepresent invention.

Only those raw cokes which have a volatile matter content within therange of about 8 to about 20 percent, 10 to 20 percent if used as soleactive particulate material) or which in a separate step aredevolatilized so that the volatile contents are in this range, and, morepreferably, in the range of about I 1 percent to about [6 percent, canbe employed in the processes of the present invention. With cokes havingvolatile matter contents in excess of about 20 percent (water not beingincluded in this figure) difficulty is generally encountered in thecarbonization step due to excessive fusibility. Raw cokes havingvolatile contents of about 10 percent or less (when used without anycoal) present difficulty in that they fail to alloy or interact with theplasticizing agent. Raw cokes low in sulfur are also preferred.

When the raw coke as obtained has a volatile matter content above about20 percent it can be heated under controlled conditions, which shouldavoid localized overheating, to reduce the volatile matter content tocome within the ranges specified. This can be done at relativelylow-temperatures of about 500-l,000 F. Care should be taken thatoxidation does not occur and that the volatile matter content is notreduced to a point below that of the ranges set forth.

The plasticizer should be neither substantially vaporizable (atatmospheric pressure) nor substantially thermally decomposable belowabout 490 F., which temperature is well above the temperature at whichthe alloying effect of the plasticizer with the raw coke and/or coalgenerally occurs. Suitable substances for plasticizers include coal tar,coal tar fractions, coal tar pitches, certain high-boiling hydrocarbonoils and residues produced in catalytic cracking of petroleumdistillates such as thermal tar, petroleum pitch, wood tar pitch,anthracene oil, heavy wood tar oils and pitches, heavy lignite tar oilsand pitches, phenanthrene, and the like. Heavy petroleum hydrocarbonresidues and asphalts, whether cracked or straight run, may also be usedas plasticizers.

The selection of a plasticizing agent (which may also be referred to asa plasticizer or alloying agent) depends upon a number of factors suchas the material(s) with which it is alloyed, its cost, etc. Anyplasticizer which will partially alloy with the raw coke and/or coalused can be used. Not all are exactly equivalent. Aromatic hydrocarbonsare preferred. The oxygen or nitrogen derivatives of aromatichydrocarbons are also useful, but are less desirable than thehydrocarbons. The plasticizer should not contain substantial amounts ofsubstances which decompose to give strongly oxidizing decompositionproducts. Cycloparaffinic hydrocarbons or their derivatives may be used,for example, the furfural extract of heavy lubricating oils. Mixtures ofthe hydrocarbons and their derivatives may be used to advantage in manyinstances.

Preferably, as previously pointed out, the plasticizer should notvaporize or decompose substantially below about 490 F. Of course, in thecarbonizing operation a certain amount of volatile hydrocarbons andother byproducts resulting from the pyrolysis of the plasticizer areobtained, but the most desirable plasticizers are those which areconverted to a large extent into coke. Excessive production of vaporsand gases tend to unduly increase the porosity of the coke bodies.However, in view of the small proportion of plasticizer used which isnever greater than about 8 percent, and in view of the fact that someporosity in the bodies produced is desirable, this is not generally aproblem. High-sulfur content materials are generally undesirable becausemetallurgical coke having a high-sulfur content is frequentlyobjectionable to the user of the coke.

The comminuted coal and/or raw coke and the plasticizer can bepreliminarily mixed at room temperature where this is convenient,particularly if the plasticizer is in finely divided solid condition.Likewise those plasticizers which are normally liquid can be mixed coldwith the coal and/or coke. Or the mixing can be carried out at elevatedtemperatures such as by heating the coal or coke, or a fairly uniformmixture of coal and/or raw coke and plasticizer, to a temperature aboveabout 300 F. and typically in the range of about 320500 F. and moretypically 340-450 F and the mixing step carried out in any suitable typeof equipment, so that mixing and plasticizing or alloying take placesimultaneously. The proper time-temperature for this alloying treatmentis quite critical and will vary depending upon the volatile mattercontent of the coal and/or raw coke and the particular plasticizeremployed and its viscosity. in any case, the plasticized particlesshould not be heated for too long a period of time and/or to too high atemperature before they are pressure-formed since it is possible thatsuch treatment will render the plasticized particles nonplastic andresult in difficulties in fonning the green bodies, or in green bodiesof poor strength. These time-temperature conditions, or holding times atmaximum temperature can readily be established for any given mixturedescribed herein and using the guidelines discussed herein, using thebriquettability of the plasticized particles and the properties of thebaked briquets as criteria. The alloying treatment should preferably becarried out in a nonoxidizing atmosphere, particularly when or after theplasticized particles approach or reach their maximum temperature.

In certain instances, the mixing can be carried out with the rawmaterials warmed, e.g. to l0O-200 F., but at a temperature below that atwhich the alloying effect is initiated or complete and this followed byfurther processing at a higher temperature.

As stated care must be taken that the alloying treatment is controlledso that it does not proceed too far. This usually can be controlled bythe temperature used, although time has a substantial effect. If amixture of a plasticizer and coal and/or raw coke is heated while mixingat a temperature above the range given, or above the maximum desirabletemperature for that particular mixture, it goes through first a pastyform and then the mixture changes in character and becomes too dry toextrude and difficult to mold such as by a continuous roll briquettingoperation. In other words, the plasticized coal and/or raw coke shouldfurnish its own lubrication effect on the dies. With certainplasticizers, this over treatment may occur in the temperature rangegiven if the time is extended too long, for example, beyond 5 minutes oreven less. As previously indicated, the criticality of the time andtemperature relationship in the alloying step varies with the amount andkind of plasticizer employed. It also varies, with the volatile mattercontent and particle size of the coal and/or raw coke. In general,however, the small or line coal and/or raw coke particles which aretypically employed in the present invention alloy rapidly because of thelarge surface area and small diameter of the particles.

If the alloyed mixture has gone to a point beyond that readilyextrudable or moldable, the mixture not only becomes difficult to rollbriquet or extrude, but also results in the formation of bodies whichmay develop imperfections and be of Petroleum coke Parts I percent rawpetroleum coke with a VM of 15 percent, or 18 percent or if theparticulate material were 50 percent coal, etc. Also, as previouslyindicated, if raw petroleum coke of 8 or 9 percent VM content isemployed, it will not be used alone but will typically be used inconjunction with substantial amounts of coal. it is apparent also thatthe time and temperature conditions may vary for such coke formulationsas the following, all of which are embraced within the invention andwithin the drawings depicting same:

Bituminous coal llasticizer (parts per hundred parts of coke and coal)VM VM (percent) Parts (percent) Asphalt. Anthracene oil. Thermal tar.Petroleum pitch. Thermal tar.

Thermal tar. Coal tar pitch. Coal tar. Thermal tar. Coal tar.

Coal tar pitch. Thermal tar. Coal tar. Thermal tar.

1 In the foregoing formulations h, k. l, m, n, o and p, the bituminouscoal was partially devolatillzed prior to blending (in order that the VMcontent of the coal-petroleum coke mixtures would not exceed about 20%)before it was blended with the petroleum coke and processed inaccordance with the steps of this invention. In all cases in thealloying heating step, the particles will be heated long enough (withinthe time ranges previously set forth) and/or to a sufliciently hightemperature (also within the previously discussed temperature ranges) tobring about the desired softening and alloying efiect, but not so longand/or to such high temperatures that the alloy formed is renderednon-plastic. a V

Plasticized coals or raw cokes that may be employed in this processmust, after being pressure-formed or briquetted, be of a character inwhich there is little plastic and no liquid flow during any stage of thecarbonizing operation. If the coals or coke have too high a volatilematter content or if the plasticized mixtures tend to melt and flowbefore decomposition of the decomposable components of the formed greenbodies has occurred, the minute channels from the interior of the bodiesto the exterior by which the decomposition vapors escape will tend toseal off, resulting in processing problems in the carbonizing step andthe production of large pores and carbonized bodies of poor strength.However, when prepared with the materials having the propertiespreviously described and according to the methods outlined, such flowdoes not occur and the vapor escape channels remain small and uniformlydispersed throughout the bodies being carbonized, so that the gases canescape rapidly and without the production of large pores or channels.

As previously indicated, if it is desired to use a coal having avolatile matter content of from about 20 percent upwards to about 45percent in the present process, in an amount such that the resultantblend (coal plus raw petroleum coke) would have a volatile mattercontent higher than about 20 percent by weight, then it is necessary topartially devolatilize such coals by any suitable means known to thoseskilled in the art, so that the volatile matter content of the resultantblend is no higher than about 20 percent. If this partialdevolatilization of the coal operation results in excessiveagglomeration of the coal, it may be preliminarily crushed to reduce itto a reasonable size, after which it can then be used as a raw materialin the present process.

All of the materials in the blend to be briquetted or pressure formedare generally heated to approximately the same temperature, In theprocess of doing this, however, the various ingredient(s) will beaffected differently. For example, if a substantially inert materialsuch as anthracite is used, it will typically merely be heated up tooperating temperatures; on the other hand the coal and/or raw petroleumcoke blended with the plasticizer undergo an alloying effect. The timeand/or temperature the particles are kept in or heated to in thisheating step also depend upon a number of factors in addition to thosealready discussed. For example, if the particulate material being heatedis l00 percent raw petroleum coke (viz no coal or inert) having avolatile matter (VM) content of about l2 percent, the conditions aredifferent than if it were The forming apparatus 20 or rolls of thebriquetting machine may be at any desired temperature, such as atapproximately the same temperature as the particles or higher, or atroom temperature, or at a temperature intermediate of these, etc. Thebriquetting rolls may be water cooled, or oil cooled, etc. The heatedsolids prior to briquetting must be protected from undue atmosphericoxidation which is detrimental to the strength of the finished product.it is also apparent that in the presence of excess air there is dangerof ignition and combustion. An inert gas atmosphere may be provided.

As previously indicated, the pressure employed in the forming step isvariable depending on the temperature of the plasticized particles beingfonned, the formulation being processed, the type of press or formingoperation used, etc. [in a piston press it will be between about 500 andabout 15,000 p.s.i., employing lower pressures with higher temperaturesand vice versa. in a roll press, the pressure (P) will typically bebetween about 4,000 and about 90.000 p.s.i., where P =F/A (A total areaof pockets under pressure along the line of contact between the rolls; FForce applied to the rolls of the press).] For example, blendtemperatures of 300-350 F. and pressures of 1,000 to 2,000 p.s.i. in apiston press may result in poor green and/or baked body strengths,whereas temperatures of 350-450 F. and pressures of 500 p.s.i. canresult in bodies of good strength. Typically, no more pressure should beemployed than will produce a formed green body having a porosity of atleast 8 percent, while on the other hand, at least as much pressureshould be employed so as to produce a green body having a porosity nogreater than 37 percent In other words, if the porosity of the formedgreen body is under 8 percent or is higher than 37 percent, or is not asatisfactory level, whatever is desired, then the pressure employed maybe reduced or increased accordingly until the porosity of the resultantgreen bodies is at the desired level. Green body porosities betweenabout 15 percent and about 30 percent are more typical and preferred.

A roll-press is most preferred for volume production and when such aforming apparatus is employed the "pressing time" (the time when thealloyed particles being shaped are actually under pressure or whenpressure is actually applied) is usually less than 2 seconds andtypically less than one. Other fonning apparatus can be employed, suchas previously discussed.

in piston presses, pressures less than 2,500 p.s.i. are most typicaland, generally, pressures higher than this are wasteful of energy. Withmany of the carbonaceous blends or compositions of the presentinvention, particularly those having a relatively high VM content, whenpressures above about 3,500 p.s.i. are employed, an increasingpercentage of the briquets or formed articles have flaws (particularlyafter they are carbonized). Pressures above about 4,000 p.s.i. whenusing a piston press are generally avoided, therefore, unlesssignificant amounts of inerts have been added to the mixture to beprocessed, or unless the composition or mixture to be processed has alow-VM content in which cases the use of such higher pressures may beadvantageous. Higher pressures are used in roll presses.

A minimum porosity of at least 8 percent should be maintained in theformed green body in order that a minimum of problems arising in theforming and carbonizing steps and in order that the carbonizing step maybe carried out in a rapid operation. if the porosity of the formedbodies is too low and attempts are made to rapidly carbonize suchbodies, then the escaping remaining volatiles tend to rupture thearticles and produce coke of unsuitable size or strength formetallurgical purposes.

Changing the temperature to which the alloyed particles are heated, ormaking changes in the formulation which is employed to make the greenbodies also, of course, affect the porosity of the bodies produced. Asaforesaid, the maximum porosity of the formed green bodies is 37percent. lf higher than this, then they are too weak or have too low anapparent density (after being carbonized) for their contemplated uses.The apparent density of the carbonized product is generally betweenabout 1.0 and 1.5 g./cc. With regard to the apparent density of theformed green bodies, this should be between about 0.85 and 1.25 g./cc.;of course the lower density bodies have the higher porosity and thehigher density green bodies have the lower porosity.

After the alloyed or plasticized particles are pressurefonned, theformed green bodies preferably are also substantially immediatelycarbonized, without substantial cooling. This is because if thetemperature of the formed material is permitted to drop very muchbetween the forming and carbonizing steps, undesirable cracks or flawsare much more likely to develop in the formed articles than if they arecarbonized immediately without any substantial cooling.

in the preferred operation wherein the particles are initiallyseparately heated before being mixed with a heated plasticizer, theoverall cycle is such that the operation typically requires no more thanabout minutes in heating the particles to a temperature between 300 and500 F., mixing them with the plasticizer, press-forming the alloyedparticles while they are still at an elevated temperature between about300 F. and about 500 F. (viz little or no colling being permitted beforethe forming operation) and getting the formed articles into thecarbonizer. During these phases of the process, no substantial surgesare permitted in the cycle. In other words, the carbonaceous particlesbeing heated or the formed carbonaceous masses being processed are keptmoving very uniformly or regularly, with no substantial buildup beingpermitted. However, there may be surges" in any preceding preheating(bringing the particles up to a given relatively low temperature such asabout 200 F.) step, which might be employed, or (within limits) in thesubsequent carbonizing step, without adverse, or as much adverse, effectupon the quality of the product produced, or the freedom from troublesof the process.

By closely following the process steps heretofore described, thepress-formed bodies may be rapidly (e.g. much faster than the 18-24hours typically required by the prior art byproduct coking oven methods)carbonized, such as to a temperature of between about l,000 and about2,000 F. (or to a product VM content of 5 percent or less) within aperiod of 8 hours maximum, without impairment of the qualities of theproduct. Carbonizing periods of from 3 to 6 hours are typical. Of coursea longer period than 8 hours may also be employed, but it will usuallybe disadvantageous to do so.

The formed green bodies generally do not resoften and stick to eachother, or deform upon being processed in the hot carbonizer 22 becauseof their having been alloyed" and pressure-formed into separate anddistinct shapes, during which a strong cohesive bond within the formedgreen bodies has been effected. Therefore, the bonds between theparticles in the individual formed bodies are very good and thecarbonized bodies produced are typically of superior strength. Withcertain formulations and under certain conditions, however, there may bea tendency for the briquets to adhere to each other. if there is atendency for the briquets to stick to each other during carbonization,they may be subjected to a brief or limited surface oxidation to set andprevent resoftening of their surfaces during carbonization.

The formed green bodies may be carbonizing in any suitable carbonizingapparatus capable of providing a substantially inert or nonoxidizingatmosphere. For best results, however, the carbonizing apparatus 22 isso constructed, or so regulated, that the formed green bodies can beraised to the desired final carbonizing temperature in a well regulatedmanner. In other words, if the desired final temperature is l,472 F.(800 C.) and the formed green bodies are at a temperature of 400 F. whenthey leave the forming apparatus 20 and enter the carbonizer 22, theypreferably will be heated from the 400 F. (or about 204 C.) temperatureto the 800 C. (1,472 F.) temperature at a very closely controlled upheatrate or upheat rates, such as at a rate not exceeding 400 C. per hour upto a temperature between about 500 C. and about 650 C. and then at arate not exceeding 500 C. per hour up to the final 800 C. temperature.In other words, slower upheat rates are typically employed until theformed green bodies reach a critical temperature or until they arepermanently set (typically 600-700 C.) after which somewhat fasterupheat rates to the desired end temperatures can be employed. Theforegoing type of heating procedure must be employed rather than aheating procedure which would subject the hot formed bodies to a sharpor widespread temperature differential, such as from a temperature of200 C. immediately to a temperature of 800 C. It is preferable, also,that the temperature of the formed bodies be increased substantiallylinearly within any given time interval. For example, this meansproceeding fairly evenly at an upheat rate not exceeding about 10 C. perminute for any given minute during the initial upheat rate which doesnot exceed 400 C. for any given hour, and at an upheat rate notexceeding about 13 C. per minute for any given minute during the upheatrate which does not exceed 500 C. per hour, rather than heating thebodies, for example, for 1 hour at 500 C., then transferring them to azone at 600 C. for another hour, etc.

Controlled temperature gradients which are more gentle than theforegoing such as not exceeding 300 C. for any given hour increment oftime, or 8 C. for any given minute increment of time, (for example, abaking rate of 3 C. per minute) are more typical or representative ofthose generally used in the carbonizing step. The particular upheat ratewithin the foregoing described ranges which will be chosen and employedwill also be dependent upon the density, porosity, size, shape and VMcontent of the formed green bodies being processed.

Rotary kilns, shaft kilns and moving grates, with gradually increasingtemperature zones as the formed bodies proceed through the carbonizer,and capable of providing a substantially inert atmosphere, are verysuitable for accomplishing the foregoing type of heating.

After the formed bodies are heated to the desired temperature, theytypically are then gradually cooled in an inert atmosphere until theyreach a temperature of about 220 F. or lower. A single piece ofapparatus, with heating zones and cooling zones, may be employed forboth carbonizing and cooling, or cooling may be accomplished in aseparate piece of equipment. The cooled formed coke (which may be storedin a product bin or immediately shipped, or immediately used in a cupolaor blast furnace, etc.

Generally, carbonizing temperatures at least as high as about l,000 F.are required and temperatures higher than this such as at l,472-l ,760F. are preferred for optimum properties. Temperatures higher than l,760F., such as up to about 2,000 E, may also be employed but will generallynot be required in order to make a satisfactory commercial product.

The volatile matter (VM) content of the raw cokes and coals of thisinvention are determined in accordance with the A.S.T.M. Procedure No.D271-48 as modified for peat and lignite, and being exclusive of water.In accordance with this procedure, a relatively small sample of the rawcoke or coal is 'heated at 950 C for a period of time between about tominutes. The difference in weight of the sample prior to and afterheating constitutes the volatile content" of the material tested. Aspreviously stated, it is preferable that the raw cokes employed in theinvention not only have the specified VM content of between about 8 andabout 20 percent and more typically between about i l and about 16percent when used with coal, or of at least about 10 percent when usedalone, but that they also form a hard, coke agglomerate or button" whilebeing heated in accordance with the previously mentioned A.S.T.M.procedure, except that a 5 gram sample instead of a 1 gram sample isused. This latter property is essential when the raw coke is employed asthe sole active particulate ingredient.

Having thus described the nature of our invention and the uses for theproduct of our invention, but being illustrated only by the appendedclaims with respect to the scope of the invention,

We claim:

1. A process for making shaped metallurgical coke bodies whichcomprises:

A. forming a mixture from (a) a blend of active carbonaceous materialsconsisting of from to 85 parts by weight of fusible coal particleshaving a volatile matter content of at least about 15 percent and from85 to 15 parts by weight of particles of raw, uncalcined coke made bycoking a heavy liquefiable, hydrocarbon to a volatile matter contentexclusive of water of about 8percent to about percent, the sum of theparts of coal and the parts of raw coke equaling 100; and (b) from about1 to about 8 parts of a plasticizing agent by weight of the coal and rawcoke particles, said plasticizing agent being neither substantiallyvaporizable nor substantially thermally decomposable below about 490 F.,the average volatile matter content of the coal and raw coke particlestaken together not exceeding about 20 percent, and said coal and rawcoke each being agglomerative when heated and alloyed according to stepB following:

B. at least partially alloying said plasticizing agent with said coaland raw coke particles to convert said coal and coke particles to amaterial which is plasticlike by heating the materials comprising saidmixture, which includes the plasticizing agent, for a period of not morethan 15 minutes in a substantially inert gas system to a temperature atleast as high as about 300 F. and below about 500 F., which is below theagglomerative temperature of the particles of each of the base coal andcoke materials before the materials are mixed with the plasticizer;

C. compressing the hot plasticlike mixture in a substantially inert gassystem while it is still plastic and above about 300 F., but below theagglomerative temperature of particles of each of the base coal and cokematerials, employing a pressure above about 500 p.s.i. to form shapedgreen bodies which have an AD. of at least 0.85 g./cc. and a porosity nogreater than 37 percent; and

D. carbon izing said shaped bodies in a substantially inert gas systemwith a gradual upheat rate to between about 1,000 F. and 2,000 F.

2. A process according to claim 1 wherein said raw uncalcined coke isdelayed coker raw petroleum coke.

.3. A process according to claim 1 wherein an inert material is added tothe mixture to be compressed, in amounts up to pans per [00 parts ofblend of coal, raw coke and inert and wherein the parts of plasticizingagent employed is based, by weight, upon the parts of blend of coal, rawcoke and the inert material.

4. A process according to claim 1 wherein between 2 and 6 parts ofplasticizing agent is employed in the mixture to be compressed.

5. A process according to claim 1 wherein said plasticizing agent isthermal tar.

6. A process according to claim 1 wherein the maximum temperature towhich the mixture is heated in step B is between about 320 F. and about500 F. and wherein the time that the mixture is maintained at maximumtemperature prior to being compressed in step C is no more than about 5minutes.

7. A process according to claim 1 wherein the compressing step C iscarried out by means of a roll briquetting operation using a pressingtime of no more than two seconds.

8. A process according to claim 1 wherein said coal and raw cokeparticles are heated before being mixed with the plasticizing agent.

9. A process according to claim 8 wherein said plasticizing agent isheated before being mixed with the coal and raw coke particles.

10. A process according to claim 8 wherein said coal and raw cokeparticles are heated by entrainment heating of the particles in an inertgas stream and wherein the heated particles are separated from the inertgas before being mixed with the plasticizing agent.

11. A process for making shaped metallurgical coke bodies whichcomprises:

A. forming a mixture comprised of 100 parts of fusible coal particleshaving a volatile matter content of at least about 15 percent and nohigher than about 20 percent, and from about i to about 8 parts of aplasticizing agent by weight of the coal, said plasticizing agent beingneither substantially vaporizable nor substantially thermallydecomposable below about 490 F., and said coal being agglomerative whenheated and alloyed according to step B following;

B. at least partially alloying said plasticizing agent with said coal toconvert said coal to a material which is plasticlike by heating thematerials comprising said mixture which includes the plasticizing agent,for a period of not more than 15 minutes in a substantially inert gassystem to a temperature at least as high as about 300 F. and below about500 F., which is below the agglomerative temperature of the particles ofthe base coal before it is mixed with the plasticizer;

C. compressing the hot plasticlike mixture in a substantially inert gassystem while it is still plastic and above about 300 F., but below theagglomerative temperature of the particles of the base coal, employing apressure above about 500 p.s.i. to form shaped green bodies which havean AD. of at least 0.85 g./cc. and a porosity no greater than 37percent; and

D. carbonizing said shaped bodies in a substantially inert gas systemwith a gradual upheat rate to between about 1,000 F. and 2,000" F.

12. A process according to claim 11 wherein raw uncalcined coke made bycoking a heavy liquefiable hydrocarbon to a volatile matter contentexclusive of water of about 8 percent about 20 percent is added to themixture to be compressed, in amounts up to 15 parts per 100 parts ofcoal.

13. A process according to claim 11 wherein an inert material is addedto the mixture to be compressed, in amounts up to 25 parts per 100 partsof blend of coal and inert and wherein the parts of plasticizing agentemployed is based, by weight, upon the 100 parts of blend of coal andthe inert material.

14. A process according to claim 1] wherein between 2 and 6 parts ofplasticizing agent is employed in the mixture to be compressed.

15. A process according to claim 11 wherein said plasticizing agent isthermal tar.

16. A process according to claim 11 wherein the maximum temperature towhich the mixture is heated in step B is between about 320 F. and about500 F. and wherein the time that the mixture is maintained at maximumtemperature prior to being compressed in step C is no more than aboutminutes.

17. A process according to claim 11 wherein the compressing step C iscarried out by means of a roll briquetting operation using a pressingtime of no more than 2 seconds.

18. A process according to claim 11 wherein said coal particles areheated before being mixed with the plasticizing agent.

19. A process according to claim 18 wherein said plasticizing agent isheated before being mixed with the coal.

20. A process according to claim 18 wherein said coal particles areheated by entrainment heating of the particles in an inert gas streamand wherein the heated particles are separated from the inert gas beforebeing mixed with the plasticizing agent.

21. A process for making shaped metallurgical coke bodies whichcomprises:

A. forming a mixture comprised of 100 parts of raw, uncalcined cokeparticles made by coking a heavy liquefiable, hydrocarbon to a volatilematter content exclusive of water of about percent to about 20 percent,and from about 1 to about 8 parts of a plasticizing agent by weight ofthe raw coke particles, said plasticizing agent being neithersubstantially vaporizable nor substantially thermally decomposable belowabout 490 F., and said coke being agglomerative when heated and alloyedaccording to step B following;

B. at least partially alloying said plasticizing agent with said rawcoke particles to convert said coke particles to a material which isplasticlike by heating the materials com prising said mixture whichincludes the plasticizing agent, for a period of not more than 15minutes in a substantially inert gas system to a temperature at least ashigh as about 300 F. and below about 500 F which is below theagglomerative temperature of the particles of the base coke materialbefore it is mixed with the plasticizer;

C. compressing the hot plasticlike mixture in a substantially inert gassystem while it is still plastic and above about 300 F., but below theagglomerative temperature of the particles of the base coke material,employing a pressure above about 500 p.s.i. to fonn shaped green bodieswhich have an AD. of at least 0.85 g./cc. and a porosity no greater than37 percent; and

D. carbonizing said shaped bodies in a substantially inert gas systemwith a gradual upheat rate to between about l,000 F. and 2.000 F.

22. A process according to claim 21 wherein said raw uncalcined coke isdelayed coker raw petroleum coke.

23. A process according to claim 21 wherein fusible coke having avolatile matter content of at least about 15 percent is added to themixture to be compressed, in amounts up to 15 parts per I00 parts of rawuncalcined coke; the average volatile matter content of the raw cokeparticles and of the coal taken together not exceeding about 20 percent.

24. A process according to claim 21 wherein an inert material is addedto the mixture to be compressed, in amounts up to 25 parts per I00 ofblend of raw coke and inert and wherein the parts of plasticizing agentemployed is based, by weight, upon the parts of blend of raw coke andthe inert material.

25. A process according to claim 21 wherein between 2 and 6 parts ofplasticizing agent is employed in the mixture to be compressed.

26. A process according to claim 21 wherein said plasticizing agent isthennal tar.

27. A process according to claim 21 wherein the maximum temperature towhich the mixture is heated in step B is between about 320 F. and about500 F. and wherein the time that the mixture is maintained at maximumtemperature prior to being compressed in step C is no more than about 5minutes.

28. A process according to claim 21 wherein the compressing step C iscarried out by means of a roll briquetting operation using a pressingtime of no more than 2 seconds.

29. A process according to claim 21 wherein said raw coke particles areheated before being mixed with the plasticizing agent.

30. A process according to claim 29 wherein said raw coke particles areheated by entrainment heating of the particles in an inert gas streamand wherein the heated particles are separated from the inert gas beforebeing mixed with the plasticizing agent.

2. A process according to claim 1 wherein said raw uncalcined coke isdelayed coker raw petroleum coke.
 3. A process according to claim 1wherein an inert material is added to the mixture to be compressed, inamounts up to 25 parts per 100 parts of blend of coal, raw coke andinert and wherein the parts of plasticizing agent employed is based, byweight, upon the 100 parts of blend of coal, raw coke and the inertmaterial.
 4. A process according to claim 1 wherein between 2 and 6parts of plasticizing agent is employed in the mixture to be compressed.5. A process according to claim 1 wherein said plasticizing agent isthermal tar.
 6. A process according to claim 1 wherein the maximumtemperature to which the mixture is heated in step B is between about320* F. and about 500* F. and wherein the time that the mixture ismaintained at maximum temperature prior to being compressed in step C isno more than about 5 minutes.
 7. A process according to claim 1 whereinthe compressing step C is carried out by means of a roll briquettingoperation using a pressing time of no more than two seconds.
 8. Aprocess according to claim 1 wherein said coal and raw coke particlesare heated before being mixed with the plasticizing agent.
 9. A processaccording to claim 8 wherein said plasticizing agent is heated beforebeing mixed with the coal and raw coke particles.
 10. A processaccording to claim 8 wherein said coal and raw coke particles are heatedby entrainment heating of the particles in an inert gas stream andwherein the heated particles are separated from the inert gas beforebeing mixed with the plasticizing agent.
 11. A process for making shapedmetallurgical coke bodies which comprises: A. forming a mixturecomprised of 100 parts of fusible coal particles having a volatilematter content of at least about 15 percent and no higher than about 20percent, and from about 1 to about 8 parts of a plasticizing agent byweight of the coal, said plasticizing agent being neither substantiallyvaporizable nor substantially thermally decomposable below about 490*F., and said coal being agglomerative when heated and alloyed accordingto step B following; B. at least partially alloying said plasticizingagent with said coal to convert said coal to a material which isplasticlike by heating the materials comprising said mixture whichincludes the plasticizing agent, for a period of not more than 15minutes in a substantially inert gas system to a temperature at least ashigh as about 300* F. and below about 500* F., which is below theagglomerative temperature of the particles of the base coal before it ismixed with the plasticizer; C. compressing the hot plasticlike mixturein a substantially inert gas system while it is still plastic and aboveabout 300* F., but below the agglomerative temperature of the particlesof the base coal, employing a pressure above about 500 p.s.i. to formshaped green bodies which have an A.D. of at least 0.85 g./cc. and aporosity no greater than 37 percent; and D. carbonizing said shapedbodies in a substantially inert gas system with a gradual upheat rate tobetween about 1,000* F. and 2,000* F.
 12. A process according to claim11 wherein raw uncalcined coke made by coking a heavy liquefiablehydrocarbon to a volatile matter content exclusive of water of about 8percent to about 20 percent is added to the mixture to be compressed, inamounts up to 15 parts per 100 parts of coal.
 13. A process according toclaim 11 wherein an inert material is added to the mixture to becompressed, in amounts up to 25 parts per 100 parts of blend of coal andinert and wherein the parts of plasticizing agent employed is based, byweight, upon the 100 parts of blend of coal and the inert material. 14.A process according to claim 11 wherein between 2 and 6 parts ofplasticizing agent is employed in the mixture to be compressed.
 15. Aprocess according to claim 11 wherein said plasticizing agent is thermaltar.
 16. A process according to claim 11 wherein the maximum temperatureto which the mixture is heated in step B is between about 320* F. andabout 500* F. and wherein the time that the mixture is maintained atmaximum temperature prior to being compressed in step C is no more thanabout 5 minutes.
 17. A process according to claim 11 wherein thecompressing step C is carried out by means of a roll briquettingoperation using a pressing time of no more than 2 seconds.
 18. A processaccording to claim 11 wherein said coal particles are heated beforebeing mixed with the plasticizing agent.
 19. A process according toclaim 18 wherein said plasticizing agent is heated before being mixedwith the coal.
 20. A process according to claim 18 wherein said coalparticles are heated by entrainment heating of the particles in an inertgas stream and wherein the heated particles are separated from the inertgas before being mixed with the plasticizing agent.
 21. A process formaking shaped metallurgical coke bodies which comprises: A. forming amixture comprised of 100 parts of raw, uncalcined coke particles made bycoking a heavy liqUefiable, hydrocarbon to a volatile matter contentexclusive of water of about 10 percent to about 20 percent, and fromabout 1 to about 8 parts of a plasticizing agent by weight of the rawcoke particles, said plasticizing agent being neither substantiallyvaporizable nor substantially thermally decomposable below about 490*F., and said coke being agglomerative when heated and alloyed accordingto step B following; B. at least partially alloying said plasticizingagent with said raw coke particles to convert said coke particles to amaterial which is plasticlike by heating the materials comprising saidmixture which includes the plasticizing agent, for a period of not morethan 15 minutes in a substantially inert gas system to a temperature atleast as high as about 300* F. and below about 500* F., which is belowthe agglomerative temperature of the particles of the base coke materialbefore it is mixed with the plasticizer; C. compressing the hotplasticlike mixture in a substantially inert gas system while it isstill plastic and above about 300* F., but below the agglomerativetemperature of the particles of the base coke material, employing apressure above about 500 p.s.i. to form shaped green bodies which havean A.D. of at least 0.85 g./cc. and a porosity no greater than 37percent; and D. carbonizing said shaped bodies in a substantially inertgas system with a gradual upheat rate to between about 1,000* F. and2,000* F.
 22. A process according to claim 21 wherein said rawuncalcined coke is delayed coker raw petroleum coke.
 23. A processaccording to claim 21 wherein fusible coal having a volatile mattercontent of at least about 15 percent is added to the mixture to becompressed, in amounts up to 15 parts per 100 parts of raw uncalcinedcoke; the average volatile matter content of the raw coke particles andof the coal taken together not exceeding about 20 percent.
 24. A processaccording to claim 21 wherein an inert material is added to the mixtureto be compressed, in amounts up to 25 parts per 100 parts of blend ofraw coke and inert and wherein the parts of plasticizing agent employedis based, by weight, upon the 100 parts of blend of raw coke and theinert material.
 25. A process according to claim 21 wherein between 2and 6 parts of plasticizing agent is employed in the mixture to becompressed.
 26. A process according to claim 21 wherein saidplasticizing agent is thermal tar.
 27. A process according to claim 21wherein the maximum temperature to which the mixture is heated in step Bis between about 320* F. and about 500* F. and wherein the time that themixture is maintained at maximum temperature prior to being compressedin step C is no more than about 5 minutes.
 28. A process according toclaim 21 wherein the compressing step C is carried out by means of aroll briquetting operation using a pressing time of no more than 2seconds.
 29. A process according to claim 21 wherein said raw cokeparticles are heated before being mixed with the plasticizing agent. 30.A process according to claim 29 wherein said raw coke particles areheated by entrainment heating of the particles in an inert gas streamand wherein the heated particles are separated from the inert gas beforebeing mixed with the plasticizing agent.